ISO Standards to determine wool yarn strength
Wool yarn strength depends on many factors, including the type of wool, the way the yarn is spun, and the number of plies. The strength of wool yarn can be measured using a tensile tester, which applies force to the yarn until it breaks. The maximum force required to break the yarn is recorded as its tensile strength.
Wool yarn strength can vary widely. Here's a breakdown of the key ISO standards that determine wool yarn strength and what they cover:
ISO 2062: Textiles - Yarns from packages
Determination of single-end breaking force and elongation at break using constant rate of extension (CRE) tester
- This is the most relevant ISO standard for determining wool yarn strength.
- It specifies a method for measuring the breaking force (how much force is needed to break the yarn) and elongation at break (how much the yarn stretches before breaking) of yarn.
- It uses a Constant Rate of Extension (CRE) tester, which is the most common type of tensile testing machine.
Why is ISO 2062 important?
- Quality control: It helps ensure that wool yarn meets the required strength and elongation standards for its intended use.
- Performance prediction: The results can be used to predict how the yarn will perform in fabrics or other textile products.
- Comparison: It provides a standardized method for comparing the strength of different wool yarns.
Other relevant ISO standards
ISO 2062:2009: Textiles - Yarn from packages
Determination of linear density (mass per unit length) by Skein method. This standard is used to determine the linear density of the yarn, which is related to its fineness or coarseness. Linear density can influence yarn strength. This is the primary standard for testing the breaking force and elongation of yarns, including wool. It is suitable for single yarns (spun or filament). It uses a constant rate of extension (CRE) tester, such as an Instron tensile tester.
ISO 2061: Textiles - Determination of twist in yarns - Direct counting method
This standard is used to determine the amount of twist in the yarn. Twist is a crucial factor affecting yarn strength.
ISO 6939:1988: Textiles - Yarns from packages
Method of test for breaking strength of yarn by the skein method
This standard describes a method for determining the breaking strength of yarn in skein form, which can be useful for certain applications. It focuses on the tenacity (strength per unit linear density) of staple fiber yarns like wool and uses a CRE or CRT (Constant Rate of Traverse) tester.
ISO 5079:2023: Textile fibres -Determination of breaking force and elongation at break of individual fibers
Although primarily for fibers, this standard helps assess the strength of individual wool fibers before spinning into yarn.
These ISO standards are widely used in the textile industry for quality control and evaluating performance of the wool yarns.
ISO 13934-1: Textiles -- Tensile properties of fabrics -- Part 1: Determination of maximum force and elongation at maximum force using strip method
While ISO 2062 focuses on single yarns, ISO 13934-1 measures the tensile strength of woven fabrics, which is relevant for understanding how wool yarn performs in a final textile product.
This standard outlines the strip method, where a rectangular strip of fabric is pulled until it breaks.
ISO 13938-1: Textiles -- Bursting properties of fabrics -- Part 1: Hydraulic bursting method
This standard is used to measure the bursting strength of knitted fabrics, which is another important property for wool yarn used in garments like sweaters. It describes the hydraulic bursting method, where pressure is applied to the fabric until it bursts.
Adhering to these ISO standards can help wool yarn manufacturers and users ensure consistent quality, facilitate trade, and have confidence in the performance of their products.